The subject matter herein relates generally to feeder devices that eliminate return drag on a fed object.
In typical terminal crimping systems, a terminal and a wire are both fed to a crimping zone of an applicator. The applicator includes crimp tooling that defines the crimping zone. The crimp tooling is configured to mechanically crimp the terminal to the wire to produce an electrical lead. The terminal crimping systems may use a wire feeder device and/or a terminal feeder device to deliver the respective wire and terminals to the crimping zone for each crimping operation. Some wire and terminal feeder devices use a linear indexing feed member that moves linearly in a feed direction and in an opposite return direction. The feed member of such feeder devices is designed with the purpose of selective engagement of the feed object (such as the wire or the terminal). For example, the feed member engages the feed object as the feed member moves in the feed direction to advance the feed object toward the crimping zone, while the feed member disengages the feed object as the feed member moves in the return direction. Thus, although the feed member indexes back and forth between an advanced position and a retracted position, the object that is being fed should only move in one direction, the feed direction.
In some feeder devices, the feed member is forced downwards against the fed object as the feed member moves in the feed direction by a biasing member, such as a torsion spring. The force applied to the feed member by the biasing member must be strong enough to overcome friction forces and tension from the source of the fed object (for example, a bulk wire source). On the return stroke, though, the strong force applied by the biasing member may not allow the feed member to completely disengage from and clear the fed object as the feed member moves in the return direction. The feed member, for example, may scrape the wire that is being fed, and the scraping may be sufficient to damage the wire by removing a protective coating on the wire or even severing at least part of the conductive core of the wire.
Additionally, the feed member may pull back on the fed object which interferes with the position of the fed object in the crimping zone, even causing the object to move backwards at least partially out of the crimping zone. Such interference in the position of the fed object by the movement of the feed member in the return direction may cause the fed object, whether it be the wire or the terminal, to misalign with the other of the wire and the terminal in the crimping zone. Electrical leads have to meet very strict lead specifications and quality standards. A wire that is not properly located in either the side-to-side or front-to-back directions relative to the terminal, and vice-versa, will not meet the lead specifications and are usually discarded. Leads that do not meet the specifications are discarded, which wastes time and materials. Therefore, in some known linear indexing feeder devices, the feed member moving in the return direction damages the fed object and/or interferes with the position of the object in the crimping zone, which degrades the quality of the resulting produced lead.